Viral Syndrome and Post Radiation side effects

I finished radiation therapy for breast cancer fourteen months ago.  On October 29, 2005 I went to the doctor with a low grade fever, swollen lymph nodes throughout my body, head ache, generalized body pain and extreme disabling fatigue.  Her diagnosis was viral syndrome.  Since then I've had it three more times, and since my doctor is part of a large practice, I haven't seen the same doctor twice.  They all diagnose it as viral syndrome.  The last doctor suggested that it might be Epstien-Barr, but the tests came back negative for both Epstien-Barr and Cytomeglo virus.  In a chat with other breast cancer survivors some of the women explained to me that it may just be a long term side effect of radiation treatment that tends to happen a year to eighteen months after treatment ends.  They call it Radiation Flu.  Viral Syndrome sounds to me like they have evidence that I have something, but don't want to be bothered with it, and Radiation Flu sounds like something these women might have made up.  Are either of these conditions real? Should I accept this diagnosis, or begin challenging it to try to find out what is going on?  Thank you for your in-put.

[CCF-RN,MSN-rf]

Dear emiliasdance:  As radiation therapy is a localized therapy, it is rare to have such generalized side effects other than fatigue - and this usually occurs during the radiation.  I am not aware of "radiation flu."  Certainly, the symptoms you describe sound viral.  A viral infection is one in which there is no evidence of a bacterial infection but the symptoms are the same.  The primary difference between a bacterial infection and viral infection is the use of antibiotics.  Antibiotics treat bacteria but do nothing for viruses.  Viruses can also last a long time but generally resolve on their own.  If your symptoms have persisted, it may be worth seeing your primary care doctor to see if there is anything else going on.